Boat protective cover



FIG. 1 is a right side view in elevation of the design for a boat cover;

FIG. 2 is a left side view in elevation;

FIG. 3 is a front view in elevation;

FIG. 4 is a top plan view of the design; and,

FIG. 5 is a bottom plan view of the design.

The ornamental design for a boat protective cover, as shown anddescribed.